2022, Vol. 26 ›› Issue (25): 3980-3985

Comparison of effects of exosomes secreted by different mesenchymal stem cells for the treatment of osteoarthritis

Wang Xianfeng, Ou Xin, Deng Biyong   

Abstract: BACKGROUND: Mesenchymal stem cells, as seed cells in tissue engineering, have shown powerful curative effect for the treatment of osteoarthritis in the past few decades, and many registered clinical experiments have been carried out in China. More studies have shown that mesenchymal stem cells that play a therapeutic role in vivo release exosomes through paracrine function.  
OBJECTIVE: To compare the effect of bone marrow mesenchymal stem cell exosomes and umbilical cord mesenchymal stem cell exosomes on the treatment of osteoarthritis.
METHODS: Bone marrow mesenchymal stem cell exosomes and umbilical cord mesenchymal stem cell exosomes were isolated by ultra-centrifugation. Nanosight, transmission electron microscopy, and western blot assay were used to identify exosomes. Chondrocytes were co-cultured with interleukin-1β to simulate osteoarthritis in vitro. The effects of bone marrow mesenchymal stem cell exosomes and umbilical cord mesenchymal stem cell exosomes on the proliferation, apoptosis and extracellular matrix secretion of chondrocytes were evaluated by CCK-8 assay, western blot assay, and qPCR. Collagen II collagenase was injected to induce rat osteoarthritis model and the efficacy of in vivo injection of exosomes was evaluated by macroscopic evaluation and histological staining. The concentrations of interleukin-1β and tumor necrosis factor-α of joint fluid were examined by ELISA.  
RESULTS AND CONCLUSION: (1) Both kinds of exosomes were cup-shaped or round-shaped with particle size of 105-120 nm, and expressed characteristic proteins CD63, CD81, and TSG1010. (2) The yield and purity of umbilical cord mesenchymal stem cell exosomes were higher than those of bone marrow mesenchymal stem cell exosomes. (3) Both exosomes could alleviate the inflammatory effect of interleukin-1β on chondrocytes, which was mainly manifested in promoting proliferation, inhibiting apoptosis, and increasing the secretion of extracellular matrix. Among them, umbilical cord mesenchymal stem cell exosomes had stronger cartilage repair activity. (4) After the treatment of both exosomes, the macroscopic performance and OARSI score of articular cartilage were better than those of the control group, and the inflammatory factors in the joint fluid were decreased, among which the efficacy of umbilical cord mesenchymal stem cell exosomes was better than that of bone marrow mesenchymal stem cell exosomes. (5) Results suggest that the yield and purity of umbilical cord mesenchymal stem cell exosomes are higher than that of bone marrow mesenchymal stem cell exosomes, and the therapeutic effect of umbilical cord mesenchymal stem cell exosomes on the treatment of osteoarthritis is better than that of bone marrow mesenchymal stem cell exosomes. Therefore, umbilical cord mesenchymal stem cell exosome is more suitable as a new strategy for osteoarthritis.
Key words: stem cells, osteoarthritis, mesenchymal stem cells, bone marrow mesenchymal stem cell exosomes, umbilical cord mesenchymal stem cell exosomes, exosomes, cartilage, regeneration